Needle actuating camming for circular knitting machines

ABSTRACT

In a circular knitting machine wherein multi-butt needles are controlled by camming defining a plurality of raceways, the height of cam sections and the length of the needles is shortened by the provision of preliminary raise cams which are extended to also serve as guard cams and prevent the accidental descent of needles between vertical arrays of rotatably adjustable cams. Each of the adjustable cams may be positively locked in a position to permit needles to welt or in positions to raise needles to a knit or a tuck level from which they may be lowered by a main stitch cam engageable with the same needle butts as the preliminary raise and guard cams. Tilting of the needles in a vertical plane perpendicular to the camming is prevented by a needle engageable member at each feed.

CIRCULAR KNITTING MACHINES Inventor: Lester Mishcon, Miami Beach, Fla.

Assignee: The Singer Company, New York,

NY. I Filedz May 16, 1972 Appl. No.: 253,720

Related U.S-L Application Data Continuation-in-part of Ser. No. 248,518, April 28, 1972.

References Cited UNlTED STATES PATENTS United States Patent 1 1 3,780,539 Mishcon Dec. 25, 1973 NEEDLE ACTUATING CAMMING FOR 3,696,640 10/1972 Kawase et al 66/57 2,679,737 6/1954 Pierre 66/50 Primary Examiner-W. C. Reynolds Assistant Examiner-A. M. Falik Attorney-Marshall J. Breen et al.

[5 7 ABSTRACT In a circular knitting machine wherein multi-butt needles are controlled by camming defining a plurality of raceways, the height of cam sections and the length of the needles is shortened by the provision of preliminary raise cams which are extended to also serve as guard cams and prevent the accidental descent of needles between vertical arrays of rotatably adjustable cams. Each of the adjustable cams may be positively locked in a position to permit needles to welt or in positions to raise needles to a knit or a tuck level from which they may be lowered by a main stitch cam engageable with the same needle butts as the preliminary raise and guard cams. Tilting of the needles in a vertical plane perpendicular to the camming is prevented by a needle engageable member at each feed.

- 7 Claims, 3 Drawing Figures KNITTING MACHINES CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a continuation in part application claiming an invention disclosed in a prior application for Delayed-Action Auxiliary Stitch Cam of Lester Mishcon Ser. No. 248,5l8, filed Apr. 28, 1972.

BACKGROUND OFTHE INVENTION 1. Field of the Invention The invention relates to circular knitting machines and more particularly to needle actuating camming defining a plurality of raceways for multi-butt needles.

2. Description of the Prior Art It is known to provide circular knitting machines with multi-butt needles and a vertical array of singleselection needle raising cams plus a stitch cam at each feed, and to separately guard each of the cams to define a restricted raceway for each needle butt. In a vertical array each raise cam heretofore was designed to lift needles from a cast-off position to a tuck position or to lift needles from a cast-off position to a knit position. Since each raise cam was constructed to raise needles from the cast-off position, considerable vertical space was needed to accomodate such cams when a substantial number were employed and as a consequence long needles were required. 1

SUMMARY OF THE INVENTION In accordance with the invention I provide camming for actuating multi-butt needles at each feed of a circula'r knitting machine including a vertical array of adjust able needle-raising cams, a stitch cam and a preliminary raise cam, the preliminary raise being engageable with a butt common to all needles to raise the needles a substantial distance from their cast-off position to a position which is somewhat lower than their full tuck position. Because of the preliminary raise cams, the necessity of designing raise cams to lift needles all the way from a cast-off position to a full tuck position or to a knit position is eliminated and the height of needle actuating camming which includes a large number of cams in vertical arrays of cams may be reduced, as may the length of the interacting needles. Such preliminary raise cams extend across the camming for each feed to define the lowest possible level to which needles may descend in the arrangement of the invention and so render it unnecessary to otherwise guard cams against the accidental descent of needles. The tilting of needles in a vertical plane perpendicular to the needle actuating camming is prevented by a single needle engageable member at each feed. Because of the adjustable cams disposable in knit, tuck or welt positions camming operations may be altered without it being necessary to remove cam sections froma machine and change cams.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a cam section according to the invention and cooperating knitting needles;

FIG. 2 is another perspective view of the cam section of FIG. 1.

FIG. 3 is a fragmentary cross-sectional perspective view showing a portion of the cam section of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, reference character 10 designates a cam section according to the invention for actuating knitting needles moving in the direction indicated relative to the cam section such as the needles 12, 14, 16 and 18 having correspondingly located butts 20, 22, 24 and 26 and having other butts 28, 30, 32 and 34. The cam section includes a preliminary raise cam 36, a vertical array of rotatably adjustable cams 38, 40, 42 and 44, and a stitch cam 45 rendered adjustable as in the manner shown and described in U. S. Pat. No. 3,525,239 for Cam Adjustment Apparatus for a Circular Knitting Machine issued Aug. 25, 1970 to Harry Agulnek. The preliminary raise cam engages the correspondingly located butts 20, 22, 24 amd 26 to raise all needles from a cast-off position to a substantially higher position which is nevertheless lower than a full tuck position, and after having been'so raised by the preliminary raise cam a needle may be further raised to its full tuck or knit position by the engagement of other butts with the rotatably adjustable cams or not depending upon the position of said rotatably adjustable cams.

Each of the rotatably adjustable cams is securable in one of three positions. In FIG. 1 the rotatably adjustable cam 38 is shown in one such position wherein it may engage butt 28 and raise needle 12 to a knit position. Cam 40 is shown in another such position, a position to miss butt 30 and so permit needle 14 to move across the cam without being further raised, and cam 42 is shown in still another position, a position to engage butt 32 and raise needle 16 to a full tuck position. The position of cam 44 is similar to the position of cam 38 so that it may engage butt 34 and raise needle 18 to a knit position. Since needles are raised from a cast-off position to knit or tuck in two steps, that is, first by the preliminary raise cam and then by a rotatably adjusted cam, the required cam track distance for the rotatably adjustable cams is reduced over what would be required in the absence of the preliminary raise cam.'The adjustable cams can therefore be located close together and the height of the cam section as well as the length of needles minimized.

Each of the rotatably adjustable earns 38, 40, 42 and 44 is movable into and securable in each of the three mentioned positions. As shown each of the cams 38, 40 42 and 44 is at one end of a shaft, that is, the shafts 46, 48, and 52 respectively which extend through the cam sections and have reduced opposite end portions 54, 56 58 and 60 that include screw driver slots 62, 64, 66 and 68 by means of which the shafts and associated cams may be turned. Locking means including the members 70, 72 74 and 76 are provided for securing the earns 38, 40, 42 and 44 respectively in each of the aforesaid three positions. Such locking means is identical for each of the rotatably adjustable cams and is shown in detail for cam 38 in FIG. 3. As shown in FIG. 3 shaft 46 includes key-ways 78, 80 and 82 suited to receiving a key 84 located at one end of member which is pivoted on a shaft 86-affixed in the cam section 10. The key 84 is biased toward the slots by a spring 88 which acts on the member 70 and holds the key in one or another of the key-ways when the key and a key-way are in alignment to thereby secure the shaft 46 and so lock cam 38 in one of the three positions hereinbefore indicated. The key 84 may be disengaged from a keyway by pushing on the member 70 at 87 and while the key is disengaged, shaft 46 may be turned to align the key with another key-way after which the member may be released to permit the spring 88 to move the key into the newly aligned slot.

In the cam section the uncontrolled downward or upward flight of needles is prevented at all points across its width. In FIG. 1 the preliminary raise cam 36 is shown extending across the camming in the cam section 10 as an extension 90, substantially to the edge of the cam section 10 and serves as a guard cam to prevent the uncontrolled downward flight of needles travelling across the cam section. A guard cam 92 prevents the uncontrolled upward flight of needles moving between the preliminary raise cam 36 and stitch cam 45. Also, needles are prevented from rocking in a vertical plane perpendicular to earn section 10 by a member 94 which is affixed to and extends across the cam section, and which is engageable with the lower end portions of the shanks of needles. Ordinarily, as the needle is acted upon by either the preliminary raise cam or by the adjustable cam, there would be a tendency for the needle to rock about the butt being acted upon. The lower portion of the needle would thus tend to pivot inwardly towards the outer face of the cam section. By providing member 94 the lower ends of the needles are inhibited in movement towards such face of the cam section, thereby minimizing the amount of rocking which may occur.

The height to which needles are raised by the preliminary raise cam 36 is such that any needle not further raised by a rotatably adjustable cam comes into contact with and is lowered to a welt position in advance of the stitch cam 45 by cam 96 on wing cam structure 98. The cam structure 98 also includes the cam 100 which defines a restricted pathway of constant dimension with the stitch cam 45 regardless of the position of the stitch cam. The wing cam structure is constructed and functions as in the manner shown and described in U. S. Pat. No. 3,457,736 for Wing Cam for Pattern Wheel 'Knitting Apparatus issued July 29, 1969 to Lester Mishcon. As indicated the wing cam structure is pivoted in the cam section 10 at 102.

While the invention has been described in its preferred force, it is to be understood that the words which have been used are words of description rather than of limitation, and that changes within the purview of the appended claims may be made without departing from the true scope and spirit of the invention.

Having thus set forth the nature of this invention, what is claimed herein is:

1. In a multi-feed circular knitting machine, the combination comprising multi-butt cylinder needles and camming for each of a plurality of feeds to actuate the cylinder needles, said camming including a preliminary raise cam extending across the camming at each of said feeds to contact one butt of every one of the needles and raise said needles to a predetermined less than latch-clear and higher than welt position height and prevent the descent of any of said needles below said height, a plurality of vertically spaced rotatable adjustable cams each cooperable with a different needle butt which is other than said one butt, each adjustable cam being rotatable to one position to raise needles an additional amount to tuck height, to another position to raise needles an additional amount to a latch-clear position, andto still another position permitting needles to welt, and a stitch cam disposed to contact the said one butt of the needles and lower said needles to a castoff position below said predetermined height.

2. In a multi-feed circular knitting machine, the combination comprising a multi-butt cylinder needle and camming for each of a plurality of feeds to actuate the cylinder needle, said camming including a preliminary raise cam extending across the camming at each of said feeds to contact one butt of every one of the needles and raise said needle from a cast-off position through part of the vertical distance between the cast-off and tuck height of the needle to a predetermined higher than welt position height and prevent the descent of any of said needles below said height, at least one rotatable adjustable cam to contact another butt of said needle and raise said needle an additional amount to at least tuck height, and a stitch cam disposed to contact the said one butt of the needle and lower said needle to a cast-off position.

3. The combination of claim 2 wherein the adjustable cam is rotatable to one position to raise the needle to tuck height and to another position to raise the needle to a latch-clear position.

4. The combination of claim 3 wherein the adjustable cam in addition to being positionable in the one position to raise the needle to tuck height and in another position to raise the needle to a latch-clear position, is also positionable in a position permitting the needle to welt, and said combination includes means for locking the adjustable cam in each of the said positions.

5. The combination of claim 2 including a wing cam disposed to define a raceway for directing said one butt of the needle to a welt position.

6. The combination of claim 5 wherein the preliminary raise cam extends under the stitch cam, and the wing cam is between the stitch cam and preliminary raise cam.

7. The combination of claim 2 including a laterally extending member located a substantial distance below the preliminary raise cam and engageable with the needle shank to prevent the needle from pivoting on the preliminary raise cam. 

1. In a multi-feed circular knitting machine, the combination comprising multi-butt cylinder needles and camming for each of a plurality of feeds to actuate the cylinder needles, said camming including a preliminary raise cam extending across the camming at each of said feeds to contact one butt of every one of the needles and raise said needles to a predetermined less than latch-clear and higher than welt position height and prevent the descent of any of said needles below said height, a plurality of vertically spaced rotatable adjustable cams each cooperable with a different needle butt which is other than said one butt, each adjustable cam being rotatable to one position to raise needles an additional amount to tuck height, to another position to raise needles an additional amount to a latch-clear position, and to still another position permitting needles to welt, and a stitch cam disposed to contact the said one butt of the needles and lower said needles to a cast-off position below said predetermined height.
 2. In a multi-feed circular knitting machine, the combination comprising a multi-butt cylinder needle and camming for each of a plurality of feeds to actuate the cylinder needle, said camming including a preliminary raise cam extending across the camming at each of said feeds to contact one butt of every one of the needles and raise said needle from a cast-off position through part of the vertical distance between the cast-off and tuck height of the needle to a predetermined higher than welt position height and prevent the descent of any of said needles below said height, at least one rotatable adjustable cam to contact another butt of said needle and raise said needle an additional amount to at least tuck height, and a stitch cam disposed to contact the said one butt of the needle and lower said needle to a cast-off position.
 3. The combination of claim 2 wherein the adjustable cam is rotatable to one position to raise the needle to tuck height and to another position to raise the needle to a latch-clear position.
 4. The combination of claim 3 wherein the adjustable cam in addition to being positionable in the one position to raise the needle to tuck height and in another position to raise the needle to a latch-clear position, is also positionable in a position permitting the needle to welt, and said combination includes means for locking the adjustable cam in each of the said positions.
 5. The combination of claim 2 including a wing cam disposed to define a raceway for directing said one butt of the needle to a welt position.
 6. The combination of claim 5 wherein the preliminary raise cam extends under the stitch cam, and the wing cam is between the stitch cam and preliminary raise cam.
 7. The combination of claim 2 including a laterally extending member located a substantial distance below the preliminary raise cam and engageable with the needle shank to prevent the needle from pivoting on the preliminary raise cam. 